GB1574608A

GB1574608A - Reservoirs for vehicle hydraulic systems

Info

Publication number: GB1574608A
Application number: GB26255/76A
Authority: GB
Original assignee: Girling Ltd
Current assignee: Girling Ltd
Priority date: 1976-06-24
Filing date: 1976-06-24
Publication date: 1980-09-10
Also published as: US4166431A; ES460086A1; AU2539377A; AU507424B2; DE2728308A1

Description

PATENT SPECIFICATION

( 21) Application No 26255/76 ( 22) Filed 24 June 1976 ( 23) Complete Specification filed 11 May 1977

( 44) Complete Specification published 10 Sept 1980

U ( 51) INT CL 3 B 60 T 11/22 ( 52) Index at acceptance F 2 F 801 FA ( 72) Inventor JOHN FLORY PICKERING ( 11) 1574608 ( 19) ( 54) IMPROVEMENTS IN RESERVOIRS FOR VEHICLE HYDRAULIC SYSTEMS ( 71) We, GIRLING LIMITED, a British Company of Kings Road, Tyseley, Birmingham, 11, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:-

This invention relates to improvements in reservoirs for vehicle hydraulic systems of the kind comprising a container for hydraulic fluid of which at least a part is transparent or translucent so that the level of the contents is externally visible, and the container is provided with a filler opening adapted to be closed by a detachable closure cap and through which the container can be filled with hydraulic fluid.

In a vehicle hydraulic system a reservoir of the kind set forth can be mounted directly on the body of a pedal-operated hydraulic master cylinder for a brake or clutch system Alternatively the reservoir can be remote from the master cylinder and be connected thereto through an external connection.

It is a problem that when a reservoir of the kind set forth is filled to the brim with hydraulic fluid and then the filler opening is closed by the closure cap, when the closure cap incorporates a bulky assembly such as liquid level contents indicator, the contents indicator displaces fluid which overflows from the container This is undesirable since conventional hydraulic fluid is highly penetrative and can remove body paint from a vehicle.

Some known reservoirs of the kind set forth include a ridge or like mark located on the transparent or translucent part of the container as an indication of the desired fluid level However, due to the limited space considerations, when the reservoir is installed in an engine compartment sometimes the ridge or like mark is not readily ' visible from above, or is obscured by other engine components Also any dirt accumulating on the ridge may give rise to misrepresentation of the true level of liquid.

According to our invention in a reservoir of the kind set forth the container comprises 50 a continuous side wall, and a top wall incorporating the filler opening, at least one integral portion of the top wall being depressed and forming a window, and the said one portion and at least a part of the sur 55 rounding area being transparent or translucent, and the internal face of the window lies in a plane spaced below a plane containing the internal face of the said part of the surrounding area, and defines a pre 60 determined level so that the reservoir can be filled with hydraulic fluid until, at the predetermined level, the hydraulic fluid is in visible contact with the internal face of the window, with the internal face of the 65 said part of the surrounding area untouched by the hydraulic fluid.

Since the window is located in the top wall it is visible from above and is unlikely to be obstructed, particularly since the reser 70 voir must always be installed in a position which the filler opening is accessible.

As the window is located in a depression a volume normally unoccupied by liquid is defined between the internal face of the 75 window and the internal face of the remainder of the top wall Thus when the container comprises the reservoir of an hydraulic system, this volume is chosen such that it is sufficient to accommodate any hy 80 draulic fluid which may be displaced from the container upon insertion of a liquid level contents indicator Of course, the volume of fluid contained in the container when the fluid is in visible contact on the internal face 85 of the window is sufficient for the hydraulic system Also any accumulated dirt can be readily removed from the window.

In one construction the top wall is constructed wholly of synthetic plastics 90 material which is wholly translucent or substantially transparent and two windows are provided on opposite sides of the top wall and are located in local depressions or steps at the edges thereof Conveniently the de 95 pressions comprise joggled portions which 1,574,608 are formed during a moulding process, to form the top wall.

The top wall can be incorporated in any of a series of containers of different capacities with the edge of the wall fixedly and sealingly secured to an exposed upper edge of a body constituted by the side wall.

One embodiment of our invention is illustrated in the accompanying drawings in which:Figure 1 is a plan view of a reservoir for an hydraulic braking ssytem; Figure 2 is a side elevation of the same; Figure 3 is a section on the line 3-3 of Figure 2; Figure 4 is a section on the line 4-4 of Figure 2; and Figure 5 shows on an enlarged scale a portion of Figure 4 comprising a section through one of the windows.

The reservoir illustrated in the drawings comprises a container constituted by an open-topped body 1 which is closed at its open upper end by a top wall 2 Both the body 1 and the top wall 2 comprise mouldings of synthetic plastics material which are rigidly connected together in a sealing manner by a weld or suitable adhesive to form a seam 3 The mouldings are both substantially transparent or translucent.

The body 1 is of known construction and is provided with a series of baffles which divide it into two main' compartments 4, 5 for connection through outlet ports 6 and 7 to recuperation ports in the body of a master cylinder on which the reservoir is mounted.

The top wall 2 has a generally planar closure portion 8 having a short integral peripheral outwardly stepped rim or skirt 9 which is superimposed upon and connected to the exposed upper edge of the body 1 Also the top wall is fonned with local baffle portions for connection to the free uper edge of complementary baffles in the body 1 A filler opening 10 surrounded by a threaded upstanding skirt 11 to receive a detachable closure cap leads into the compartment 5.

In accordance with our invention the top wall 2 is provided with a pair of identical windows 12 Each window 12 is located at substantially the mid-point in the length of each side edge of the top wall and in a local depression or joggle in the closure portion 8 which extends into the rim 9 to a position slightly above the step Thus the lower (internal faces) 13 of the windows 12 lie in a common plane parallel with but spaced below a plane containing the internal face 14 of the remainder of the closure portion 8.

When the reservoir is filled with hydraulic fluid through the filler opening 10 the windows 12 are clearly visible from above the container and, as the level of fluid rises, the surfaces 13 will be contacted by the fluid when a predetermined liquid level 'is reached At this point the fluid, which may be slightly coloured, shows through the windows 12 whilst the remainder of the top wall 2 appears in the natural colour of the plas 70 tics material At this level a sufficient volume is present for an hydraulic system, conveniently a braking system.

Should the filler opening 10 be closed by a closure cap embodying a liquid level con 75 tents indicator fluid displaced by the insertion of the contents indicator will be accommodated within the unoccupied volume between the two planes referred to above without any tendency for the fluid to overflow 80 Any dirt which may accumulate on the top wall can be readily removed from the windows 12.

Claims

WHAT WE CLAIM IS: -

1 A reservoir of the kind set forth in which the container comprises a continuous side wall, and a top wall incorporating the filler opening, at least one integral portion 90 of the top wall being depressed and forming a window, and the said one portion and at least a part of the surrounding area being transparent or translucent and the internal face of the window lies in a plane spaced 95 below a plane containing the internal face of the said part of the surrounding area, and defines a predetermined level so that the reservoir can be filled with hydraulic fluid until, at the predetermined level, the hy 100 draulic fluid is in visible contact with the internal face of the window, with the internal face of the said part of the surrounding area untouched by the hydraulic fluid.

2 A reservoir according to claim 1, 105 in which the top wall is constructed wholly of synthetic plastics material which is wholly translucent or substantially transparent and two windows are provided on opposite sides of the top wall and are located in local de 110 pressions or steps at the edges thereof.

3 A reservoir according to claim 2, in which the depressions comprise joggled portions which are formed during a moulding process to form the top wall 115 4 A reservoir according to claim 2 or claim 3, in which the top wall comprises a generally planar closure portion, an integral peripheral skirt, having an outward step and local baffle portions, and the skirt and 120 baffle portions are adapted to be superimposed upon and connected to complementary free upper edges of the side wall and upstanding baffles in the container, the windows extending into the skirt to a posi 125 tion above the step.

A reservoir according to any preceding claim in which the closure cap incorporates a liquid level contents indicator and 2.

1,574,608 the volume defined between the internal face of the or each window and the internal face of the remainder of the top wall is chosen such that it is sufficient to accommodate any hydraulic fluid which may be displaced upon insertion of the liquid level contents indicator.

6 A reservoir substantially as herein described with reference to and as illustrated in the accompanying drawings.

BARKER, BRETTELL & DUNCAN, Chartered Patent Agents, Agents for the Applicants, 138 Hagley Road, Edgbaston, Birmingham, B 16 9 PW.

Printed for Her Majesty's Stationery Office by Burgess & Son (Abingdon), Ltd -1980.

Published at The Patent Office 25 Southampton Buildings, London, WC 2 A l AY from which copies may be obtained.